Background: Agathosma betulina (Buchu) and Pygeum africana (Pygeum) are native Southern African plants with numerous traditional medicinal uses. However, studies on their antibacterial effects are limited. The discovery of new antibacterial treatment options has become important given the growing prevalence of bacterial resistance to common antibiotics.

Aims: To investigate the antibacterial effects of water, methanolic and ethyl acetate extracts prepared from different commercial plant materials against antibiotic-sensitive and antibiotic-resistant pathogens, and to determine their phytochemical and toxicity profiles.

Methods: Agar disc diffusion and liquid microdilution assays were used to determine the inhibitory effects of the Buchu and Pygeum extracts against common bacteria, including Staphylococcus aureus, MRSA, Escherichia coli, ESBL E. coli, Klebsiella pneumoniae and ESBL K. pneumoniae. Five different conventional antibiotics were also tested against the six bacterial species using these assays, serving as reference antibiotics. Qualitative phytochemical assays were used to identify phytochemical classes within each extract. Artemia nauplii assays were used to assess toxicities.

Results: All Buchu and Pygeum extracts prepared from the powdered commercial product, as well as the commercially supplied plant segments, were inactive in agar and liquid broth assays. All extracts were deemed to be non-toxic in Artemia.

Conclusion: Commercial supplies of Buchu and Pygeum were ineffective against all bacterial pathogens tested. While toxicity studies suggest they are safe to use in Artemia, the use of these products is brought into question due to their lack of antimicrobial activity. It is possible that extracts prepared from the fresh plant, compared to pre-processed plant material, may yield antimicrobial activities.